Japan eyes solar station in space as new energy source

Nov 08, 2009 by Karyn Poupee
This file graphic illustration released from Japan's Institute for Unmanned Space Experiment Free Flyer (USEF) shows a system of space solar power system (SSPS) which consists of a large solar power generator and transmission panel. Japan's space agency hopes to by 2030 collect solar power in space and zap it down to Earth, using laser beams or microwaves.

It may sound like a sci-fi vision, but Japan's space agency is dead serious: by 2030 it wants to collect solar power in space and zap it down to Earth, using laser beams or microwaves.

The government has just picked a group of companies and a team of researchers tasked with turning the ambitious, multi-billion-dollar dream of unlimited clean into reality in coming decades.

With few energy resources of its own and heavily reliant on oil imports, Japan has long been a leader in solar and other renewable energies and this year set ambitious reduction targets.

But Japan's boldest plan to date is the Space System (SSPS), in which arrays of photovoltaic dishes several square kilometres (square miles) in size would hover in geostationary orbit outside the Earth's atmosphere.

"Since solar power is a clean and inexhaustible energy source, we believe that this system will be able to help solve the problems of energy shortage and global warming," researchers at Mitsubishi Heavy Industries, one of the project participants, wrote in a report.

"The sun's rays abound in space."

The solar cells would capture the solar energy, which is at least five times stronger in space than on Earth, and beam it down to the ground through clusters of lasers or microwaves.

These would be collected by gigantic parabolic antennae, likely to be located in restricted areas at sea or on dam reservoirs, said Tadashige Takiya, a spokesman at the Japan Aerospace Exploration Agency (JAXA).

The researchers are targeting a one system, equivalent to a medium-sized atomic power plant, that would produce electricity at eight yen (cents) per kilowatt-hour, six times cheaper than its current cost in Japan.

The challenge -- including transporting the components to space -- may appear gigantic, but Japan has been pursuing the project since 1998, with some 130 researchers studying it under JAXA's oversight.

Last month Japan's Economy and Trade Ministry and the Science Ministry took another step toward making the project a reality, by selecting several Japanese high-tech giants as participants in the project.

The consortium, named the Institute for Unmanned Space Experiment Free Flyer, also includes Mitsubishi Electric, NEC, Fujitsu and Sharp.

The project's roadmap outlined several steps that would need to be taken before a full-blown launch in 2030.

Within several years, "a satellite designed to test the transmission by microwave should be put into low orbit with a Japanese rocket," said Tatsuhito Fujita, one of the JAXA researchers heading the project.

The next step, expected around 2020, would be to launch and test a large flexible photovoltaic structure with 10 megawatt power capacity, to be followed by a 250 megawatt prototype.

This would help evaluate the project's financial viability, say officials. The final aim is to produce electricity cheap enough to compete with other alternative energy sources.

JAXA says the transmission technology would be safe but concedes it would have to convince the public, which may harbour images of laser beams shooting down from the sky, roasting birds or slicing up aircraft in mid-air.

According to a 2004 study by JAXA, the words 'laser' and 'microwave' caused the most concern among the 1,000 people questioned.

(c) 2009 AFP

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User comments : 32

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Husky
3 / 5 (7) Nov 08, 2009
The project poses some serious challenges, like solarcell degradation from micrometeorites and ionisation and I somewhat doubt that the whole venture is viable from a pure economical point of view, but then again, it's been a long time since we've seen some really bold action in space and if nobody dares to break new ground we'd still be walking with sticks.
Edylc
2 / 5 (6) Nov 08, 2009
This is really interesting. However, has anyone ever seen a James Bond movie? I wonder if any questions will be raised about this possibly also being used as a giant death ray.
Like... Would it be possible for this to be used as a giant death ray?
Husky
1.7 / 5 (3) Nov 08, 2009
...I can see it now, some teenage hacker hijacks the controlsystems, because somebody at the lab opened a Paris Hilton email. This contrapture must not in any way come in physical contact with internet traffic, how convenient it may sound for remote control, no routers, no firewalls, only its private network. There are speculations that some of the big power outtages in the u.s. may have been caused by a foreign nation testing its cyberwarfare capabillities.
Buyck
3.7 / 5 (3) Nov 08, 2009
A smart move from Japan. The country itself hase a very dense population. The open space that rest in that country is small. So there is not enough space for solar fields on land. Maybe in the sea... but they obtained for solar fields in space.
deatopmg
4.2 / 5 (6) Nov 08, 2009
This is a 40+ yr old idea. It has been studied extensively. Microwave generation, transmission, and conversion back to electricity, today, is far more efficient than any equivalent laser system. The microwave energy density passing through the atmosphere would be relatively low and thus of low toxicity to any birds flying through. However, it has never been pursued because getting all that "stuff" into orbit and assembled cannot be done cost effectively.
yyz
4.5 / 5 (2) Nov 08, 2009
deatopmg, I agree that that a cost-effective way of getting the materials for construction to the site will be a major burden. But I also worry that power transmission through MW or laser is complicated, and much more research is needed to ensure whatever methods are to be employed, safeguards must be stringently followed so as to cause no harm to the populace and the local ecosystem, something I think were're still a long ways from.
derricka
2.3 / 5 (3) Nov 08, 2009
Perhaps the first power station in orbit could help to construct successive stations, assuming the microwave beam could be focused enough to power a spacecraft craft coming up. Perhaps lasers could also be used here. The energy would be used to heat propellent gases to very high temperatures, possibly even a plasma state, like with VASIMR thrusters. Payload would be maximized, and fuel loads minimized. Future stations could then be built at far lower cost.
NeilFarbstein
4 / 5 (1) Nov 08, 2009
Current estimates project the building cost of PV solar sats to be 12 times higher than concentrating solar power plants that are already operating. The cost of CSP solar tower power electricity is expected to fall much lower than other competing types of solar energy.
NeilFarbstein
1.3 / 5 (3) Nov 08, 2009
Perhaps the first power station in orbit could help to construct successive stations, assuming the microwave beam could be focused enough to power a spacecraft craft coming up. Perhaps lasers could also be used here. The energy would be used to heat propellent gases to very high temperatures, possibly even a plasma state, like with VASIMR thrusters. Payload would be maximized, and fuel loads minimized. Future stations could then be built at far lower cost.

Interesting point. I've been designing spacecraft with external power supplies like lasers for some time. Getting funded is another matter.
Ant
2 / 5 (4) Nov 08, 2009
Still sounds like a weapon to me, lets see, hands up all those who have put their head in a microwave oven.
antialias
3 / 5 (1) Nov 08, 2009
The problem is maintenance. Once you have something in GEO then you can't send anyone to repair the damn thing once it goes on the fritz. Others have pointed out the problems of degradation and microdebris (which is much harder to avoid when you have a multi-square-kilometer installation)

It's probably way more cost effective to situate 10 solar power plants on earth around the equator.

The EU is currently trying for 15% solar power to the tune of 400 billion Euros. I'm guessing that for the same amount of money you can only get a tiny fraction of that from GEO sattelite installations like the one proposed.

Bob_Kob
2.7 / 5 (3) Nov 08, 2009
We'll have fusion by then.
otto1923
1.5 / 5 (2) Nov 08, 2009
The problem is maintenance. Once you have something in GEO then
Robots by 2020. This is japan after all. Probably want this excuse to develop the tech. Hey, 130 experts can't be wrong. Also, I agree- I think this is a big Yakuza plot for world domination. Just threatening other sats could bring the world to it's knees. Muahahahahaaa
tk1
4.7 / 5 (3) Nov 08, 2009
I saw a TV program exploring the idea of a solar station in orbit where they beamed a microwave from one mountain top to another in Hawaii to simulate the distance between space orbit and earth. The problem they had were: Focusing the microwave beam, Capturing the beam, and the energy loss in transition. The power levels received were significantly lower than those transmitted.

Think of a directional antenna broadcasting in one direction. The greater the distance the wider the wave front and the energy density will be less at any given point within the wave front.

But still a cool idea!
Sonhouse
2.7 / 5 (3) Nov 08, 2009
I think this idea will take off when the cabling research on carbon nanotubes for space elevators gets off the ground and actual elevators are built. With elevators cost of solar/microwave orbital sites come down by a factor of a thousand or more. My money is in carbon nanotube, hundreds of thousands of miles of it. It is not as far away as you think.
etim
1 / 5 (1) Nov 08, 2009
I see a big market for designer tin foil head gear...
zuggerjack
not rated yet Nov 08, 2009
The primary concern regarding this project are the biohazards associated with high-intensity microwaves, as described in the book Sunstroke by US aerospace engineer David Kagan. The US Environmental Agency is greatly worried about the microwave irradiating of human, plant and animal tissues at the satellite's ground receiver; they say that it's powerful enough to heat up living tissue. And that's at ground level. That means passengers aboard an aircraft that accidentally passes through the beam could get flash-roasted like popping a dinner into your microwave oven. Birds too. Also the EPA is concerned about atmospheric heating and telecommunications interference as the beam microwaves its way through all layers of the earth's atmosphere. In addition the microwave heating effects could exacerbate global warming.

Mercury_01
not rated yet Nov 09, 2009
The technology for this is old hat. No one should be doubting it's viability.
nuge
not rated yet Nov 09, 2009
I have some questions:
-Do they use a Maser to transmit the microwaves?
-How efficient would the beaming through the atmosphere be?
-Wouldn't microwaves heat up the water molecules in clouds?
-How are the microwaves received? Is it just an antenna?
-What happens in the event of an impact?
zuggerjack
1 / 5 (1) Nov 09, 2009
-Nuge, you're right on the mark here regarding the use of masers for transmission, according to many sources including Sunstroke author David Kagan, and Yale University tech experts.
-According to the United States Office Of Technology Assessment of space solar power-beaming, the efficiency would probably be about 17%.
- This would be more than enough to disrupt satellite and radio telecommunications, and cause substantial cloud modifications in the lower atmosphere that would negatively impact weather, and heat up the atmosphere. Not to mention the possibility that aircraft passengers could get fried, as well as people too close to the receiving station.
-The microwaves are received by rectennas that contain billions of copper dipoles.
-Please read the best-selling book titled Sunstroke (like I did) and you'll find out what happens when such a satellite is involved in a nasty impact.
otto1923
5 / 5 (1) Nov 09, 2009
- This would be more than enough to disrupt satellite and radio telecommunications, and cause substantial cloud modifications in the lower atmosphere that would negatively impact weather, and heat up the atmosphere. Not to mention the possibility that aircraft passengers could get fried, as well as people too close to the receiving station
Now- why would japan and California both spend the money to build these things if they knew for certain these major problems were unavoidable? The smaller test units will hash out these potentials and frequencies, configurations, etc will be adjusted accordingly. If insurmountable then we'll know won't we? A more appropriate tone might be 'these are potential constraints which need to be addressed' rather than 'if they build it destruction will ensue.' We hear the same attitudes from animal rights people about reindeer herds and pipelines and it only wastes time and money.
danman5000
not rated yet Nov 09, 2009
Frying people in airplanes, even if it were possible, would still be a nonissue. Just make the receiver / beam area restricted airspace like they already do for some places. They said they'd build these in remote areas anyway so it won't impact traffic much. Too bad for the birds though, but hey they shouldn't have messed with the LHC http://www.physor...873.html
El_Nose
not rated yet Nov 09, 2009
This is old like really old -- I pulled the article published a couple years ago on physorg about a similiar project with pentagon funding
http://www.physor...731.html but it is expired so I found it from another online source.

http://www.sfgate...0S32.DTL

It seems like a viable source of energy and it looks as if there may be a few nations looking into this as a realistic power adgenda.

And i figure that with three or four nations doing the tests for safety the credibility will be sufficient for the public.
jimbo92107
not rated yet Nov 09, 2009
Death-ray fun aside, if a flock of geese flew through the beam, would they land pre-cooked?
sender
1 / 5 (1) Nov 09, 2009
time to launch some heavy klystron capacitors and radiovoltaic beacons towards the solar nuclear coreolis to capture the nuclear energies and beam a relay energy pipeline back
zuggerjack
not rated yet Nov 10, 2009
A major safety issue regarding power-beaming high-intensity microwaves from satellites is quite correctly addressed in the book Sunstroke by US aerospace engineer David Kagan, and most clearly explained in the US OTA document titled "Solar Power Satellites". Otto (thank you for coming on-board again), danman, and El Nose, please be advised that the sticking point with space solar power via concentrated microwave beams from satellites is the established fact that should the power-beaming satellite's so-called "fail-safe" mechanism (that's supposed to defocus the intense microwave beam to a "harmless" power level in the event of an emergency) is very susceptible to being damaged beyond repair by collisions with micro-meteoroids, space junk, or an all-out attack by enemy anti-satellite vehicles. Such a devastating event could very well cause the solar power station to wander from its fixed orbit, while it continues to transmit its microwave beam at full power, with devastating results.
devanate
5 / 5 (1) Nov 14, 2009
It seems to me that it would be much more cost effective, less risky and easier to maintain to just blanket entire cities in solar cells.
antialias_physorg
5 / 5 (2) Nov 14, 2009
True, but then you'd have decentralized power - and this must (according to certain business interests) be avoided at all costs. In order to keep making large amounts of money power production must remain centralized and under the control of a few large investors.
Doug_Huffman
not rated yet Nov 15, 2009
Re 'ant's' microwave oven jibe; do you know how an MRI device works? Ever noticed how warm your slightly damp clothing, for instance, gets?
Doug_Huffman
not rated yet Nov 15, 2009
Another thought: the Solar Constant is defined at the outer limit of the atmosphere to be equal to 1350 Watts meter^-2. Calculate the change in Solar Constant with change in the distance from the Sun.

Who fails to do arithmetic is doomed to nonsense.
antialias
5 / 5 (1) Nov 15, 2009
'Microwave' is the name for a RANGE of frequencies. Only one of which (2,45GHz) is used in the microwave oven. That particular frequency is attuned to the water molecule. Use another frequency (slightly lower or higher) and you still have 'microwaves' but now there is no effect on water anymore (and thus no heating of animals/humans getting in the way.)

Well...as long as you don't hit the resonance frequency of other molecules that is. But these are all pretty much known and thus the problem of flocks of geese being cooked in mid-flight could be easily avoided.

zuggerjack
not rated yet Nov 17, 2009
Japan's JAXA, US NASA, US Department of Energy, US EPA and noted aerospace engineer David Kagan (author of the book Sunstroke, the bible on power-beaming space solar power to Earth) quite clearly state that the satellite microwave transmitter frequency will be precisely 2.45 gigahertz--the exact frequency that is designed to bring water molecules to a boil. Yes, Antialias, you are quite correct in stating that the solar power station's microwave transmitter frequency "is attuned to the water molecule", exactly like a microwave oven.

Thank you for your very pertinent comment in this important matter.